Timbol and Maciolek (1978) distinguished six types of channel
modifications of streams in the Hawaiian Islands.

1. Lined channel. An artificial channel having both natural
banks and stream bed replaced, usually with concrete. It may be
flat bottom or v-shaped. Representative examples are in Palolo
tributary of Manoa stream (leeward Oahu) and Ahuimanu tributary
of Kahaluu Stream (windward Oahu).

2. Vegetation removed-channel realigned.
Represented by Kapalama Stream.
3. Elevation culvert. These are conduit structures that are
comparatively short (typically <60 m), usually found under
highways. Culverts placed in this category include only those
where the culvert level is well above the water level immediately
downstream, i.e., the culvert creates an artificial waterfall. An
example of an elevated culvert is in Aolani tributary of Kaneohe
Stream (windward Oahu).
4. Revetment. Where one or both banks of the stream are
reinforced but the channel bed is not, as in Kalihi Stream
(leeward Oahu).

5. Blocked or filled-in channel. Where part of the original
channel is blocked as in Pauoa tributary of Nuuanu Stream
(leeward Oahu).

6. Extended culvert. This is a longer version of the
modification type 3, usually found in residential areas as in
Kawa Stream in Kaneohe (windward Oahu).

According to Timbol and Maciolek (1978), older examples of
stream channel modifications in Hawaii are the result of bridge
building. The oldest forms of channel modification are
clearing-realignment and revetments to reinforce stream banks.
Most of these types of modifications on Oahu Island were done in
the 1930 - 1950 period. The most significant form of modification
ecologically and numerically is the lined channel, the earliest
of which was built in 1938 at Kapalama Stream (Honolulu, Oahu).
Lined channels represent a majority of recently built
flood-control structures.